Mutual smart object certification

[void4]

It was noted that while IOT devices may have asymmetric crypto-based identifiers, it is still necessary to be sure whether the addressed device is the actual physical device that one wants to address.

Using a MUD-like recursive content structure, or, to generalize, a network reputation/certification mechanism.

E.g. the bathroom public key signs the public keys of all its contents :)

It's interesting to think about mutual certification which active components can causally prove the nearness of other smart objects.

Like an intelligent lightbulb cooperating with a camera, via flashing, physically transferring information to "prove"/let the camera infer proximity to it.

This could be useful for on-chain contracts, because these decentralized oracles could verify real world effects.